The invention relates to a composition of matter, a method of preparing same, catalyst, a method of producing the catalyst and a process of using the catalyst. In another aspect the invention relates to a particularly effective ethylene polymerization catalyst and process.
In the production of polyolefins, such as for example polyethylene, polypropylene, ethylene-butene copolymers etc., an important aspect of the various processes and catalysts used to produce such polymers is the productivity. By productivity is meant the amount or yield of solid polymer that is obtained by employing a given quantity of catalyst. If the productivity is high enough then the amount of catalyst residues contained in the polymer is low enough that the presence of the catalyst residues does not significantly affect the properties of the polymer and the polymer does not require additional processing to remove the catalyst residues. As those skilled in the art are aware, removal of catalyst residues from polymer is an expensive process and it is very desirable to employ a catalyst which provides sufficient productivity so that catalyst residue removal is not necessary.
In addition, high productivities are desirable in order to minimize catalyst costs. Therefore it is desirable to develop new and improved catalysts and polymerization processes which provide improved polymer productivities.
Accordingly, an object of the invention is a catalyst.
Another object of the invention is a polymerization process for using the catalyst capable of providing improved polymer productivities as compared to prior art catalysts.
Another object of the invention is a catalyst and a polymerization process in which the polymer produced contains catalyst residues in an amount so that catalyst residue removal is unnecessary.